Balloon apparatus and parachute associated therewith



July 6 1948-- L. P. FRIEDER ETAL l 2,444,642

` BALLOON APPARATUS AND PARACHUTE K ASSOCIATED THEREWITH Filed Deo. 18,1946 s sheets-sheet 1 INVENTORS BY m S. 9W

W s, MM

ATTORNEY July 6, 1948. L. P. FRIEDER lETAL 2,444,642

BALLOON APPARATUS AND PARACHUTE ASSOCIATED THEREWITH Filed Dec. 18, 194e3 sheets-sheet 2 aga j,.

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IN V EN TORi ATTORNEY L. P. FRIEDER ET AL BALLOON APPARATUS ANDPARACHUTE Y ASSOCIATED THEREWITH July Je, 194s.

s sheets-'sheet s Filed Dec. 18, 1946 INVENToRs BY www. S, MM.

ATTORNEY Patented July 6, 1.948

UNITED STATES PATE NT oFFi- CE B'ALLOON APPARATUS PARACHUTE ASSOCIATEDTHERE-WITH Leonard P. Frieder, Great Neck, and Walter S. Finken,Brooklyn, N.VY.; said Finken assignor to said Frieder kimputationDecember 1s, 1946,'seria1-No. 717,062

ing the load back to earth without damage thereto 4 or to personnel onthe ground.

When taking a meteorological reading. using pilot balloons, it is commonpractice to suspend various recording instruments from balloons to carrysuch instruments to a high elevation above the earth, soas to indicateand/or record various meteorologicalconditions at different altitudes.In some cases parachute apparatus .has been used in association with theapparatusaforesaid for lowering the instruments to the earth followingits elevation tothe desired altitude. These parachutes have` beenparticularly useful when aV balloon is used which willv burst or mayburst upon being expanded beyond its limit of expansion. This normallyoccurs when the balloon attains a suiiicientlyA high altitude so thatthe internal gas pressure greatly exceeds therareed atmosphere outsidethe balloon;

When using such a combination of balloon, parachute and load of thischaracter, quite frequently the balloon may pass through-cloud banks orvmoisture-laden air, which precipitates. upon the surface of or isabsorbed by the parachute fabric. This collection of moisture causes asubstantial increase in weight of the parachute. Due to this increasedweight, the maximum altitude attainable by the balloon is decreased. Theprecipitated moisture may also interfere withA the desired opening ofthe parachute to support the load and retard its descent. This isespecially true if. the parachute absorbs a substantial amount ofmoisture and thenpasses into alower temperature zone so that the fabricbecomes frozen. Whenusiner a parachute madeof paper, movement of itssurface incident to the inflation of the parachute while thus frozenwill cause the paper to rip, sothat the utility of the parachute isdestroyed.

A primary object of. the present invention is to overcome certain ofAthese diflicultiesby enclosing the parachute wholly within the balloon.`rIhis protects the parachute, duringits ascent, against the absorptionof water and against damage incident t0 freezing and tearing, etc. Inaccord;- ance with our present invention, there is providedf a balloon,which houses a parachute and hermetically seals it against outsideelements.

Al further object of the present invention' isrto provide also for. thehousing of the instrument' to be carried by the balloon within theballoon or a partl thereof.

A further object' ofi the presenti invention: is to provide for theactuation of arecording instrumentsealed within aballoonin response tothe l 2v expansion of the balloon itself. This expansion is-a functionof. the atmospheric pressure at the place-where (the balloon.I may be atany given time', as compared to a predetermined degree of ex--pansionrof the balloon at ground level. Suitable corrections fordifferent. ground.l level conditions may bev predetermined and` set onlthe' instrument. A further object of the present invention@ is`v toprovide apparatus of the character above set forth, wherein. the balloonis so constructed and arrangedy andinflated to such an extentthatlthepressure .at whichit will burst may be predetermined. The arrangementis-then such thatk on the bursting of. thev bannen, the weight of theinstrument` or load willy be` assumed by a. parachute. Up to this timethe parachute has been completely: enclosed within the balloon both asto the parachute canopy `and the shroud lines thereof.

A further'object of. the present invention-is to provide an electric:switch apparatus associated with the balloon. Such apparatus may beresponsive to somefpredetermined degree of expansion of: the yballoonlitself. It ymay also be arranged-to respond: to the burstingI of'. theballoon and the assuming of. the. support of the load.: by a para'-chute theretofore containedwithin theiballoonas aforesaid; The electricswitch may-be arranged to complete .a circuit to iactuate any desiredelec'- tricallyoperated mechanism or instrument.-

Otherandmore 'detailed objects of' the present invention-willbecomeapparent fromthe following l'speciiication and appendedclaims, whencon'-sildered' in connection with the accompanying drawings, in which:

Figure 1 isa view substantially in central'vertical section illustratinga parachute disposed within a balloon in readiness for iniiationj andascent;

Fig. 2.is afraginentary detailed view'substantially, infelevationillustrating the neckportion cfa-.balloon connectedto a load, theneckbeing closed following the inflation of the balloon;

Fig.. Bisa-fragmentary detailed view onpan enlarged scale illustratingthe connection ofthe canopy. portionof a parachute to the inside-of laballoon at a point distant from the neck thereof;

. Fig. irisA alfragmentary detailed View substantially in centralvertical section,.illust`rating the interiori of thel neck lof* aballoon arranged` for cooperation witha` parachute as aforesaidandparticularly. showing meansin which the line isstored connectingtheshroud lines of the parachute with theload. and solas to permit of theexpansionlof the balloon upon its ascent;

Fig. 5 -is azview similar-t0 Fig. 4, but on lalarger scale illustratinga-modied form ofthe invention wherein an electric switch is incorporatedin the-neck-porticnoi a` balloon, this formofvthe invention being usableeither with or Without an enclosed.parachute;`

Fig. 6 is va View substantially in transverse,

horizontal section taken on the line 6--6 of Fig. 5; I

and

Fig. '7 is a view similar to Fig; 1 showing "ay f modied form of theinvention wherein a load is itself enclosed Within the neckportionkofza..AV

balloon.

Turning now to the accompanying drawings;

and particularly to Figs. 1 to 4 thereof, we have shown a balloon I,comprising a bladderfor'di'aef .mally occurs upon the separation of thatpor- "tion of the balloon to which the parachute is -Qattached fromthatj portion to which the load is :attachedand the consequenttensioning of the line I4.

j. If desired,` the line I4 may itself be used as the means 'for bindingthe neck portion in a gastight conditiom'Fi'g. 2. As shown this line iscontinuous `from'the inside of the balloon as inphragm, which may be ofsubstantially spherical.,

contour, as shown, or alternatively of any other 4' desired shape. Thisballoon has a neck portion generally'indicated at 2. It may be inflatedwith any lighter-than-air gas or mixture thereof, such as hydrogen,helium or the like. Subsequent to the ination, the neck 2 may .beturnedupon itself as indicated at 3, in dotted lines in Fig. 1. The neckmay thereafter be suitably bound asindicated at 4, Fig. 2, to preventthe escape of the ini'lating gas. Y `v Y If desired, provision may bemade for aWeakened area or tearing line on the balloon. For this purposethere is shown a circumferential line of Weakness indicated at 5, Fig.1, boundedv by thickened or reinforced portions 6. The structure thusfar described may be considered for the purpose of the presentapplication asa part of the priora'rt.

Preferably associated with and enclosed completely Within the'balloon i,is a parachute 'I of any conventional or desired type. This'parachutemay be introduced into the interior of the balloon through the neck 2thereof prior to iniiation.

The usual parachute shroud vlines generally designated at 8 are alsoenclosed in the balloon I and are introduced thereinto withtheparachute 1. While the parachute is usually introduced into theballoon in folded form, this is not always done, and is not essentialin-accordance with the present invention.

While for some purposes it may be unnecessary that the parachutev beconnected to the inside of theballoon, it is usually preferred lthatthere be such a connectionfor reasons which will more particularlyappear hereinafter. To this end, the central portion of the canopy ofthe parachute is connected in any conventional Way to a point on theinside of ther balloon I, preferably distant from andusuallysubstantially opposite to the neck 2 thereof. As particularly shown inFigs. 1 and 3, the central portion or apex of the canopyor sail of theparachute 'I may have inner and outer'rein'forcing parts 9 suitably se-Acured thereto. Arranged to be supported from these reinforcing parts isa connecting loop of string, Wire or other desired material. The balloonitself may similarly have inner and outer reinforcing patches II and I2,respectively,

These vpatches vmay be of the same material as the balloon, or any otherdesired material. They are secured to the balloon in any suitable manneras by the use of some adhesiveor by vulcanization in the event that theballoon and patches II 'and I2 are of rubber or'rubber-containingmaterial.l As shown, the inner `patch I Ii supports a loop I3 ofsuitable material, suchas string or wire. This loop I3 may .be connectedto the loopv Illas best shown, for example, inIFig. El.l

The shroud lines of the parachute are con-- nected to the neck portionthereof by a load line I4 as best shown in Fig'. 1. Thus, if the balloondicatedat the upper portion of this gure through to the load I5.. On theother hand, the

line and load may, if desired1 be independently oonnected'to the neckportion of the balloon. A separate means may be used for binding theneck in'a condition to confineY the inflating gas Within the balloon.

l The load line I4 is usually of such length as to permit of the maximumexpansion possible for the balloon prior to the bursting thereof Withouttensioning this line. To this end a substantial length of the lineIlImay be provided within the balloon as particularly shown in Fig. 1.This will insure of there being no tension upon this line ortherethrough to the connecting point of the parachute to the balloonindicated at 9 to I3 inclusive. In some instances it may be desired thatthis additional length of the ,line I4 provided for the purposesaforesaid be not permitted to move at random within the balloon as inFig. `1. To this end the line may be coiled in a'predetermined fashionso that it may uncoil upon the progressive expansion of the balloon. Forthis purpose a shield member IIS may be disposed Within the neck portionof the balloon as shown in Figs. 1 and 4. This shield is of asubstantially hollow conical shape with annular grooves therearound forpermitting the neck portion 2 of the balloon to be bound around theshield by suitable bindingrneans shown at I'I. These binding means areseparate from the line I6 in the form of the invention shown in Fig. 4.The shield lII may further be provided with a plurality of substantiallylongitudinally extending grooves I8 on the outer surface thereof asshown in Figs. 1 and 4, to permit the substantially free passage ofiniiating gas past the shield after the shield has been bound inposition as shown in Fig. 4 by the binding means I'I. The excess lengthof the line I4 provided may be coiled Within the shield I6 asparticularly shown inFig. 4. This line will unwind from the interior ofthe coil thereof Within the shield IS. As further shown in this figure,the lower rend of the coil may be supported upon a suitable panel I9 ofpasteboard or other suitable material. This panel may be retained inposition by a conventional-metallic spring ring 20 received Within anannular groove inside the shield I6. The line I4 is shown as passingthrough a central aperture in the panel I9 for connection with the neckyor. therefrom to the load as shown, for example, in Figs. 1 or 2.

It is contemplated that under certain circumstances, it may be desirableto actuate some electrical means employed with the ball-oon and/orparachute apparatus aforesaid. Means are provided for closing anelectric circuit either upon -some predetermined degreeiof expansion ofthe Iballoon itself and prior to the bursting thereof, or upon theburstingA of the balloon.

-As shown, particularly in Figs. 5 and 6, the neck portion 2 of theballoon .I is provided with rearrange' iasmewhatmodied form-of'shield`2I." Within this'shield is arranged an electric -switch means containedwithin a housing 22l=supported 'between a pairof spaced andsubstantially parallel wall members 23 and`2.

associated with the switch to prevent suchclos- .i

'ing pending the happening Iof an event which is intended to operate toclose the circuit. As particularly shown in Figs. and 6, the-housingl221s provided with a closure 25. The closure isretained in position inthe housing `by a pair of *nuts and bolts 26 and 2l, extendingtherethrough and serving respectively as the two terminals of theswitch. Either the housing 22 and closure are both of insulated materialor at least-one of these nuts andvbolts 26 or 21 is suitably insu-.-

lated from the housing or closure thereof. The switch terminals may beconnected by suitable wirescontained within a cable 28 to any desired-means including the remaindei` of an electric circuit and particularly`including a suitablef` source of E. M. F. The character of `this circuitandthe means actuated thereby form per se no part oi the presentinvention and therefore are -not illustrated herein. The movable elementof lthe switch comprises a piece of spring wire 29-` vhaving a partcoiled around the bolt 2l as shown at 3G. One end 3l of the wire 29 isarranged Vin abutting relation Ewith a part ofthe interior of thehousing 22. The torsion of the wire 29 due to the coiled part 3l! issuch that it tends to make electrical contact with the boltfz wheneverthis actionis permitted. The wire s always in electrical contact withthe bolt 2l. A centrally located removable pin or retainer 32 isprovided, which in the position of the pin shown in Figs. 5 and 6,prevents such electrical contact fromwbeing made with the bolt 26 bypreventing the counterclockwise movement of the free end of the wire 29from the position shown in Fig. 6. Means are provided for moving the pinor retainer'32 up,

wardly out of the position shown to permit the 'closing of the switchupon the occurrence of the controlling event.

The switch may be operated in response to a predetermined expansion ofthe balloon. this purpose the pin 32 may be connected, for example,tosome predetermined part ofthe load line lll. 'Thus this line will betensioned to pull 'thepin 32 out of the path of the wire 29 when theballoon has been expanded to the predetermined desired control point.The upper end of the load lline I4, as seen in Fig. 5, is in effectconnected to fa point on the inside of the balloon distant from the neckthereof either directly, or as seen in Fig. 1, through the shroud lines8 and canopy of a parachute l. Then, as shown in Fig. Y5, the pin 32being connected to the line I4 andthe length of this line beingpredetermined, the pin will be withdrawn from the position shown in thedrawings at a time when the balloon is` expanded to some predeterminedextent.

l On the other hand, it may be desired to pull the pin 32 and thereuponto permit the closing of the electric circuit through the switchonlyvupon the bursting of the balloon. For thisoper- AThese members may vlbesecured within the shield -2l in any conven- For,-

6 ation the point of.: connection" of `the y pin 32 f to the lineM-willrbe such'that there is ample length of ithefline lill-between thepoint of connection with therpine32 and with the balloon. This willpermit-morethan the greatestpossible expansion Aloflthe'balloon prioritothe tensioning ofthe line M and thev consequent withdrawal of the pin 32from the position shown-in Figs. 5 and 6.o 'Ei-ther such -arrangement isto be considered within the purview of this invention. ATurning now tothe form of the invention shown in Fig. 'l-, there is provided a balloonIcontaining a parachute and shroud lines substanltiallyashereinabovedescribed. The parts, inso- -iaras they are the same or similar, aredesignated by the same reference characters. The

apparatus wherein a recording instrument or other apparatuscorresponding to the load is also wholly enclosed within andconsequently protected by the balloon itself.`

For this purpose, the balloon l shown in this figure is formed with anenlarged neck po-rtion33 yof such size fand conguration as to permittheintroduction therein of lan vinstrument generally designatedl. Theinternal character of this instrumenty forms per se no part'of thepresent invention and hence is not disclosed in further detail. Theinstrumentv 3d may be supportedabove a hollow bushing 35, which issuitably bound within a lowerpart-of the neck of the balloon.The-bushing is provided with a central passage 36 having lateralopenings 3l therefrom to permit of the iniiation of the balloonsubsequent to the assembly of the parts inthe position shown. Thebushing Iiis-suitably secured in a small diameter portion of the' neck33 of the balloon by'binding means 38 and serves to support theinstrument 34. The instrument-may be provided with anouter casing havinga plurality of longitudinal grooves 39 through which theinflating gasmay pass in- -to theinteriorof the balloon during the inflationthereof."v The end of the neckportion 33 of the yballoon may vbe-bentupon itself asA indicatedin dotted-lines atflli) subsequent to theinfiation. This-mechanism may thereafter be suitably bound vagainst theleakage of gas therethrough iny any desired manner, including that shownin detail "in FigjZn I In the "form'- of the invention sho-wn in thisfigure, the balloon is connected to the instrument E3ft by enclosing it.f Theinstrument may be connected tothe shroud lines 8 of the. parachuteby` the load line M asfshow-n in detailin the drawing. suitable lengthof vthis line is provided to permit of the desired maximum expansionof\-the'balloon asr aforesaid. As shown in this figure,

' 'theinstrument itself may also be protected against `moisture asstated above.

Furthermore, if desired the instrument may record or indicate thebarometric pressure at the place whe-rel'the balloon ymay be at anygiven time in response `-tothe-expansion ofthe balloon. For this purposethe load line I'd, rwhich connects through to a'pointin'the balloondistant `from the neckthereof via the shroud lines 8 and parachute 1vmay be ofsuitable lengthso that the expansion of the balloon willdirectly affect the instrument 34 when the slack in line IllA is takenup. The line may be arranged to control some mechanism 'within 'thisinstrument. The details of means for eifectingthis result are notdisclosed herein as these details form per se no part of the embodimentsof our present. invention, it wllbe obvious to those skilled in the artfrom the foregoing that interchange may be made in the apparatus sospecifically described. Other changes may be made as will suggestthemselves to those skilled in the art, and which are included withinthe appended claims. These claims are to be construed validly, asbroadly as the state of the Vprior art permits.

What is claimed is:

1. An apparatus for launching a loaded parachute, consisting of afreeballoon of the lighterthan-air type so constructed that it will burstwhen it reaches a rarified atmosphere during its ascent, a parachuteconfined Within the balloon which is freed by bursting of the balloon,and a load on the exterior of the balloon connected to the parachute insuch manner th-at descent of the load will be retarded by the parachuteafter the balloon bursts.

2. An apparatus for the purpose stated, comprising a lighter-than-airballoon consisting of a stretchable material containing alighter-thanair gas and having a yield point at which the balloon Willburst by expansion of the gas in rarified atmospheres, a `parachutewithin the balloon which is freed to retard descent of a load when theballoon bursts, a load on the exterior of the balloon, and meansconnecting the load to the parachute. Y

3. An apparatus for launching a parachute at high altitudes, comprisinga balloon constructed kof stretchable material having a bursting pointand containing enough of a lighter-than-air gas to raise the balloon andstretch it beyond said .bursting point by expansion of said gas when'thepanded beyond a yield point and containing enough of a lighter-than-airgas to raise the balloon and burst it when expansion of the said gas ina raried atmosphere expands the balloon beyond said yield point, aparachute canopy andv connected shroud lines and a load line enclosedwithin the balloon which are set free when the balloon bursts, and aload on the exterior of the balloon connected to one endv of the loadline, the other end of said load line being secured to the parachuteshroud lines.

5. An apparatus for launching a parachute `and its load, comprising aparachute canopy, a set of shroud lines and aload line, a rubber balloonenclosing said canopy, shroud lines and load line and having its Wall soconstructed that it Will burst When expanded beyond a predeterminedyield pont, a neck on the balloon through which a lighter-than-air gasmay beintroduced to inflate the balloon, one end of theV load line beingsecured within said neck and the other end of the load line beingsecured to the parachute shroud lines.

6. An apparatusv for launchingA a parachute and its load, comprising theparachute canopy.` and a set of shroud lines, a rubber balloon enclosingsaid canopy andshroud lines and. having its Wall so constructed that itwill burst 8 lwhich a lighter-than-air gas may be introduced to inflatethe balloon and which is of suiilcient length to permit folding it uponitself and securing it to conne said gas within the balloon andconstituting a means to which the load may be attached, and means forconnecting the load and the parachute shroud lines through the halloonneck.

7. An apparatus for launching a parachute .and its load, comprising arubber balloon containing enough of a lighter-than-air gas to raise theballoon and burst the balloon by expansion of the said gas when theballoon reaches a high enough altitude, a parachute canopy, shroud linesand a load line Within the balloon which are rset free when the balloonbursts, the load for the parachute being connected through the balloonto one end of the load line and the other end of the load line beingconnected to the parachute shroud lines.

8. An apparatus for launching a parachute and its load at highaltitudes, comprising a thin- Walled rubber balloon containing enough ofa lighter-than-air gas to raise the balloon and burst the balloon byexpansion of said gas when the balloon reaches a high enough altitude, aparachute sail and parachute shroud lines within the balloon which arefreed when the balloon bursts, and a load on the exterior of the balloonconnected through the balloon to the parachute shroud lines.

9. An apparatus for launching a parachute and its load, comprising aballoon shaped diaphragm containing enough of a lighter-than-air gas toraise said diaphragm and burst it by expansion of the said gas when thediaphragm reaches a high enough altitude, a parachute canopy, shroudlines and a load line Within the diaphragm which are set free when thediaphragm bursts, the load for the parachute being connected to one endof the load line and the other end of the load line being connected tothe shroud lines of the parachute.

10. An apparatus for thepurpose stated, Which comprises a balloonbladder composed of stretchable material and so constructed that it willrupture when stretched by expansion beyond the elastic limit of thematerial, a neck on the bladder through which a lighter-than-air gas maybe introduced to inflate the bladder and which is long enough to permitfolding a part of it upon itself to confine the gas Within the bladderand provide a means to which the load may be attached, a parachutecanopy having its apex attached yto the inner wall of the balloonbladder at a point opposite to said neck, shroud lines connected to theparachute canopy, a shield within the neck of the bladder having meansfor the passage of said gas past the shield in iniiating the balloonbladder, and a load line coiled within said shield and having one of itsends secured to the parachute shroud lines and its otherend securedwithin the neck of the balloon bladder.

, 1l. An apparatus for the purpose stated. which comprises a balloonbladder composed of stretcliable material and so constructed that itwill rupture when stretched beyond the elastic limit ofr the material, aneck on the bladder through which a lighter-than-air gas may beintroduced to inflate the bladder and which is long enough to permitfolding it upon itself and securing it to conne the gas within thebladder, a parachute canopy attached by its apex to the innerl surfaceof the bladder at a pointfopposite said neck, shroud lines connected tothe canopy, a load line coiled within the balloon neck having one of itsends secured within said neck and its other end secured to the shroudlines, and a shield within the balloon neck surrounding the coils of theload line and holding them against accidental displacement.

12. An apparatus for the purpose stated, comprising a balloon bladdercomposed of a stretchable material, a neck on the bladder through whicha, lighter-than-air gas may be introduced to inflate the bladder andwhich may be closed to confine the gas within the bladder, atwo-position electric switch secured within said neck so constructed andarranged that in one of said positions said switch is open and in theother thereof it is closed to close an electric circuit therethrough,means normally holding said switch in one of said two positions, aconnection between said holding means and the balloon bladder at a pointdistant from the neck so constructed that expansion of the bladderbeyond a predetermined extent will actuate said connection to releasesaid holding means and permit said switch to move to the other of saidtwo positions, and lead wires connected to the poles of the switch andextending out beyond the neck of the bladder.

13. An apparatus for the purpose stated, comprising a balloon bladdercomposed of a stretchable material, a neck on the bladder through whicha lighter-than-air gas may be introduced to inflate the bladder 'andwhich may be sealed to conne the gas within the bladder, an electricswitch secured within said neck, a retainer for holding said switch inopen position, a cord connected at one end to the retainer for releasingthe retainer by a pull on the cord to permit the switch to close, meansconnecting the other end of the cord to the inner surface of the bladderat a point opposite the neck in such a manner that expansion of thebladder by said gas to a predetermined diameter will effect theswitch-releasing pull upon the cord, and lead wires connected to theswitch and extending out beyond the wall of the neck.

14. An apparatus of the character described, comprising a balloon ofstretchable material adapted to be inflated by a lighter-than-air gas,and having a means through which such gas m'ay be introduced forinflating the balloon, a load connected to a neck portion of saidballoon, a parachute including a canopy and shroud lines, bothcompletely inside said balloon, a load line connected to said shroudlines and to the neck of said balloon and thence to said load, theparachute canopy being connected to a, point inside said balloon distantfrom the neck portion thereof, said load line being of such length as topermit the greatest possible expansion of said balloon prior to thebursting thereof without tensioning said load line, whereby said balloonmay be expanded to the bursting point before straightening out said loadline, and upon such bursting the support of the load will be assumed bysaid parachute.

15. An apparatus for the purpose stated, comprising 'a balloon ofstretchable material and having a neck portion through which alighterthan-air gas may be introduced to inflate the balloon and whichneck may be closed to coniine the gas following the inflation, aparachute disposed within said balloon and having a canopy and shroudlines, means connecting said canopy to a point on the inside of saidballoon distant from said neck, a load line connecting said shroud linesto the neck of said balloon, means associated with the neck of saidballoon for supporting a load, said load line being of such length as topermit of the maximum expansion possible for said balloon prior to itsbursting before said line is tensioned, whereby said parachute mayassume the support of said load upon the bursting of said balloon, anelectric switch secured within said neck, and means responsive to theassuming of the carrying of the load by said parachute for causing saidswitch to close to complete an electric circuit therethrough.

16. An apparatus for the purpose stated, comprising a balloon ofstretchable material and having a neck portion through which alighterthan-air gas may be introduced to inflate the balloon and whichneck may be closed to conne the gas following the inflation, a parachutedisposed within said balloon and having a canopy and shroud lines, meansconnecting said canopy to a point on the inside of said balloon distantfrom said neck, a load line connecting said shroud lines to the neck ofsaid balloon, means associated with the neck of said balloon forsupporting a load, said load line being of such length as to permit ofthe maximum expansion possible for said balloon prior to its bursting'before said line is tensioned, whereby said parachute may assume thesupport of said load upon the bursting of said balloon, an electricswitch secured Within said neck, resilient means tending to move saidswitch to a circuit closing position, a movable element normally holdingsaid switch in an open circuit position, and means operable in responseto the assuming of the carrying of said load by said parachute formoving said movable element to permit the operation of said switch bysaid resilient means to close an electric circuit therethrough.

1'7. Apparatus for the purpose stated, comprising a balloon ofstretchable material and having 'a neck portion through which alighterthan-air gas may be introduced to inilate the balloon and whichneck may be closed to conne the gas following the inflation, a parachutedisposed within said balloon and having a canopy and shroud lines, meansconnecting said canopy to a point on the inside of said balloon distantfrom said neck, la load line connecting said shroud lines to the neck ofsaid balloon, means associated with the neck of said balloon forsupporting a load, said load line being of such length as to permit ofthe maximum expansion possible for said balloon prior to its burstingbefore said yline is tensioned, whereby said parachute may assume thesupport of said load upon the bursting of said balloon, an electricswitch secured within said neck, a spring means tending to move saidswitch to a circuit-closing position, a movable pin arranged in saidswitch for holding it in an open circuit position, |and means securingsaid pin to said load line intermediate said shroud lines and said loadand at a point on said load line more distant from said load than saidelectric switch so that upon the tensioning of said load line incidentto the parachute vassuming the support of said load, said pin is movedto permit the closing of said switch to complete an electric circuittherethrough.

LEONARD P. FRIEDER. WALTER S. FINKEN.

